.TH std::chrono::operator+,std::chrono::operator-(std::chrono::year_month_day) 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::chrono::operator+,std::chrono::operator-(std::chrono::year_month_day) \- std::chrono::operator+,std::chrono::operator-(std::chrono::year_month_day)

.SH Synopsis
   Defined in header <chrono>
   constexpr std::chrono::year_month_day operator+( const
   std::chrono::year_month_day& ymd,

                                                    const                 \fI(since C++20)\fP
   std::chrono::months& dm

                                                  ) noexcept;
   constexpr std::chrono::year_month_day operator+( const
   std::chrono::months& dm,

                                                    const                 \fI(since C++20)\fP
   std::chrono::year_month_day& ymd

                                                  ) noexcept;
   constexpr std::chrono::year_month_day operator+( const
   std::chrono::year_month_day& ymd,

                                                    const                 \fI(since C++20)\fP
   std::chrono::years& dy

                                                  ) noexcept;
   constexpr std::chrono::year_month_day operator+( const
   std::chrono::years& dy,

                                                    const                 \fI(since C++20)\fP
   std::chrono::year_month_day& ymd

                                                  ) noexcept;
   constexpr std::chrono::year_month_day operator-( const
   std::chrono::year_month_day& ymd,

                                                    const                 \fI(since C++20)\fP
   std::chrono::months& dm

                                                  ) noexcept;
   constexpr std::chrono::year_month_day operator-( const
   std::chrono::year_month_day& ymd,

                                                    const                 \fI(since C++20)\fP
   std::chrono::years& dy

                                                  ) noexcept;

   1,2) Adds dm.count() months to the date represented by ymd. The result has the same
   day() as ymd and the same year() and month() as std::chrono::year_month(ymd.year(),
   ymd.month()) + dm.
   3,4) Adds dy.count() years to the date represented by ymd. The result is equivalent
   to std::chrono::year_month_day(ymd.year() + dy, ymd.month(), ymd.day().
   5) Subtracts dm.count() months from the date represented by ymd. Equivalent to ymd +
   -dm.
   6) Subtracts dy.count() years from the date represented by ymd. Equivalent to ymd +
   -dy.

   For durations that are convertible to both std::chrono::years and
   std::chrono::months, the years overloads (3,4,6) are preferred if the call would
   otherwise be ambiguous.

.SH Notes

   Even if ymd.ok() is true, the resulting year_month_day may not represent a valid
   date if ymd.day() is 29, 30, or 31.

.SH Example


// Run this code

 #include <chrono>
 #include <iostream>

 int main()
 {
     std::cout << std::boolalpha;

     auto ymd{std::chrono::day(1)/std::chrono::July/2021};

     ymd = ymd + std::chrono::months(4);
     std::cout << (ymd.month() == std::chrono::November) << ' '
               << (ymd.year() == std::chrono::year(2021)) << ' ';

     ymd = ymd - std::chrono::years(10);
     std::cout << (ymd.month() == std::chrono::month(11)) << ' '
               << (ymd.year() == std::chrono::year(2011)) << '\\n';
 }

.SH Output:

 true true true true
